Type-A zeolite has been used for many years as a major component in powder detergents. It has long been known in the art that if the zeolite has an alkalinity above normal, such higher alkalinity can be easily addressed by adjusting the acidic compounds in spray dry crutch operations.
It is common practice to ship type-A zeolite in powder form to the detergent manufactures by railcar. A long standing goal in the art has been the development of an effective way of increasing the loading capability of the zeolite per unit volume of container space. In this way it would be possible for a greater quantity of the zeolite product to be carried in a railcar or other shipping container or vessel. In addition, larger quantities of the zeolite could be stored in silos or other storage vessels both at the site of the manufacturer and at the site of the detergent producers.
Type-A zeolite particles typically range in size from about 1 micron to about 40 microns. In preliminary studies connected with this invention it was discovered that if dry particulate type-A zeolite is subjected to size reduction in, say, a hammer mill, some increase in loading capability per unit volume of container space can be achieved. However, there is a limit to which such particles can be subdivided in this manner. Once the particles reach a sufficiently small size, they tend to agglomerate and thereby form particles which are below, but which nevertheless approach, the particle size before milling or grinding.
It is thus a principal objective of this invention to find a way of increasing the loading capability of zeolite per unit volume of container space, especially in the case of type-A zeolite. It would be particularly advantageous if this objective could be achieved without any material adverse effect upon the properties of the zeolite for end use application in the manufacture of powder detergents.